A rotary mixer may be used as a soil stabilizer to cut, mix, and pulverize native in-place soils with additives or aggregates to modify and stabilize the soil for a strong base.
A rotary mixer may also be used as a road reclaimer to pulverize a surface layer, such as asphalt, and can mix it with an underlying base to create a new road surface and stabilize deteriorated roadways. Optionally, a rotary mixer can add asphalt emulsions or other binding agents to create a new road surface during pulverization or during a separate mix pass.
In a conventional rotary mixer, an operator may visually inspect the milled (or reclaimed) surface and manually adjust the speed of the rotor, and/or the front and rear doors to adjust the degree of pulverization of the milled surface. By closing the rear door, more material is held within the chamber. Traditionally, this is what an operator uses for fine adjustments of gradation. But by closing the rear door to hold more material, the machine requires more power to turn the rotor through that material, which causes the machine to travel slower.
U.S. Pat. No. 5,190,398 issued to Swisher, Jr. on Mar. 2, 1993, discloses an apparatus for pulverizing a surface such as a road and a system for adding liquid to the surface being pulverized.
A conventional rotary mixer may also include a breaker bar that controls the degree of pulverization of the milled surface. The breaker bar is fixed, so that it is not possible to adjust the degree of pulverization.